code: def _avg_pool_x(
      cluster: Tensor,
      x: Tensor,
      size: Optional[int] = None,
  ) -> Tensor:
      return scatter(x, cluster, dim=0, dim_size=size, reduce="mean")
  
file_path: pytorch_geometric/torch_geometric/nn/pool/avg_pool.py
imports: from typing import Callable, Optional, Tuple
  from torch import Tensor
  from torch_geometric.data import Batch, Data
  from torch_geometric.nn.pool.consecutive import consecutive_cluster
  from torch_geometric.nn.pool.pool import pool_batch, pool_edge, pool_pos
  from torch_geometric.utils import add_self_loops, scatter
label_desc: Use image node_id 1 for calling a global function with example usage: _avg_pool_x(cluster, x, size) and returns: scatter